Molal depression constant for a solvent is $4.0 \, K \, kg \, mol^{-1}$. The depression in the freezing point of the solvent for $0.03 \, mol \, kg^{-1}$ solution of $K_2SO_4$ is .............. $K$ (Assume complete dissociation of the electrolyte).

Which one of the following $0.06 \ M$ aqueous solutions has the lowest freezing point?

The Van't Hoff factor of $Ca(NO_3)_2$ is

$12.25 \ g$ of $CH_3CH_2CHClCOOH$ is added to $250 \ g$ of water to make a solution. If the dissociation constant of the above acid is $1.44 \times 10^{-3}$,the depression in the freezing point of water in $^{\circ}C$ is ($K_f$ for water is $1.86 \ K \ kg \ mol^{-1}$)

$5 \ g$ of $Na_2SO_4$ was dissolved in $x \ g$ of $H_2O$. The change in freezing point was found to be $3.82 \ ^oC$. If $Na_2SO_4$ is $81.5 \%$ ionised,the value of $x$ ($K_f$ for water $= 1.86 \ ^oC \ kg \ mol^{-1}$) is approximately .............. $g$ (molar mass of $S = 32 \ g \ mol^{-1}$ and that of $Na = 23 \ g \ mol^{-1}$)

In an aqueous solution of $NaCl$,the mole fraction of the solvent is $0.9$. Then,the relative lowering in vapour pressure will be ......... $atm$.